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An overview of recent progress in the research and development of micromachined devices for use in wireless communication subsystems is presented. Among the specific devices described are tunable micromachined capacitors, integrated high-Q inductors, micromachined low-loss microwave and millimeter-wave filters, low-loss micromechanical switches, microscale vibrating mechanical resonators with Q's in the tens of thousands, and miniature antennas for millimeter-wave applications. Specific applications are reviewed for each of these components with emphasis on methods for miniaturization and performance enhancement of existing and further wireless transceivers.

This is a chronicle of how the Proceedings of the IRE documented and influenced the dramatic changes in telecommunications technology and electronics that took place during the years from 1913 through 1937, the first quarter century of the Institute of Radio Engineers. During these years, the vacuum tube evolved from a laboratory device of low power and frequency into a wide variety of mass-produced tubes suitable for a wide range of power levels and frequencies. The long-wave systems that dominated initially gave way to short-wave systems for international communication and radio broadcasting enjoyed spectacular growth. Electromechanical television that was introduced in the 1920s gave way to all-electronic television in the 1930s. Proceedings papers disclosed developments that marked the advent of microwave systems and applications of the differential analyzer that set the stage for the digital computer. The impacts of World War I and of the Great Depression that began in 1929 also were reflected in the Proceedings. Military enterprise exerted a strong influence on trends in the radio-electronics industry throughout the period.

In a combination tutorial and research paper, spread-spectrum techniques for combating the effects of multipath on high-rate data transmissions via radio are explored. The tutorial aspect of the paper presents: 1) a heuristic outline of the theory of spread-spectrum antimultipath radio receivers and 2) a summary of a statistical model of urban/suburban multipath. The research section of the paper presents results of analyses and simulations of various candidate receivers indicated by the theory, as they perform through urban/suburban multipath. A major result shows that megabit-per-second rates through urban multipath (which typically lasts up to 5 µs) are quite feasible.

Nippon Telegraph and Telephone Public Corporation (NTT) initiated the world's first 30/20-GHz domestic satellite communication system for commercial use, using CS-2s launched from Japan in 1983. This system utilizes TDMA digital communication in the trunk transmission route of the public communication network, which includes interregional-center routes and main-island-to-remoteisland routes. Small transportable earth stations enable easy access to the public communication network from any place in Japan. The adoption of the 30/20-GHz band enables use of a compact on-board antenna that has a shaped beam that effectively covers the main islands of Japan. It also enables the use of high-performance, compact antennas at the earth stations. These antennas can easily be installed on the roof of telephone offices or set on motor vehicles. One apparent disadvantage of using the 30/20-GHz band is rain attenuation. However, NTT has realized a commercial system that is affected very little by rain attenuation. This was accomplished by utilizing high-performance radio equipment and by concentrating on appropriate system design. Adoption of the 30/20-GHz band is quite significant because the wide bandwidth available enables construction of high-capacity economical transmission systems. It also enables use of small antennas, which allow construction of high-speed digital direct-to-user transmission systems using small earth stations. These expand the application of the domestic satellite communication system to even small service areas. Therefore, NTT considers satellite communication to be of primary importance for its proposed digital communication network, and has begun research on a high-capacity, economical, multibeam communication satellite system using the 30/20-GHz band. This paper describes the 30/20-GHz band radio technology, digital communication technology utilizing high-speed TDMA, and operational technology in the public communication network.